Jar



Dec. ll, 1934. l, .1. MCCULLOUGH JAR Filed oct. 7, 1955 Patented 11:, 1934 UNITED STATES w83-,st

- PATENT OFFICE JAR Calif.

Application October 7,

7 Claims.

This invention relates to a well tool and relates more Aparticularly to a jarring tool for eiecting a jarring action in a Well.

In the course of drilling wells it is sometimes necessary to effect a jarring action in the well. For example, in fishing objects from a well it is sometimes necessary to jar them before they can be withdrawn. Various types of jarring tools have been proposed and used with varying degrees of success. Most tools of this character embody sections related for relative longitudinal movement adapted to be held in a contracted positionr by cooperating shoulders released through rotation between the sections or through varying the pressure on the circulating fluid to allow the sections to move apart so that-a jarring action can be obtained. It has been found diiiicult to provide cooperating shoulders which will withstand the strains to which they are subjected, and it is not altogether convenient to rotate a tool of this character while an up lstrainr is being exerted on the string to which the tool is connected.

It is ageneral object of the invention to provide a simple, practical and dependable tool for eiecting a jarring action within-fa well.

It is another object of the invention to provide a jarring tool in which the sections related for relative longitudinal movement are held in a contracted vposition by a means which is automatically released upon a predetermined strain being imparted to the tool.

It is another object of the invention to provide a jarring tool that may be operated without rotation and without varying the pressure on the circulating iluid. The tool provided by the present invention is fully operable by simple reciprocation of the operating string in which it is connected.

1t isanother object of the invention to provide a control means for releasably holding the sections of a jarring tool in the contracted position which is effective and dependable in operation and which is not subjectv to rapid deterioration or wear.

It is afurther object of the invention to pro-.l

vide a jarring tool of the character mentioned that can be adjusted or set to trip or operate upon any desired strain being exerted on the operating string.

Other object sl and features of my invention will be best and more fully understood from the following detailed description of a typical form and application of the invention, through- 1933, Serial No. 692,634

(Cl. Z55-27) out which description reference is had to the accompanying drawing, in which;

Fig. 1 is a longitudinal detailed sectional View of the tool provided by this invention illustrating it in the unoperated or contracted position. Fig. 2 is a view similar to Fig. 1 illustrating the tool in the operated or jarred position. Fig. 3 is an enlarged transverse detailed sectional view taken as indicated by line 3-3 on Fig. 1. Figs. 4 and 5 are enlarged transverse detailed sectional views taken as indicated by lines 4-4 and 5 5 respectively, on Fig. 1, and Fig. 6 is an enlarged transverse detailed sectional view being a View taken as indicated by line 6 6 on Fig. 2.

The tool provided by the present invention in'- cludes, generally, two main sections A and B related or connected for limited relative longitudinal movement and control or latch means C for releasably holding the sections A and B in the contracted position.

The body sections A and B form a unit or assembly adapted to be connected between the object to be jarred and an operating string. The tool may be arranged adjacent the shing tool to engage the object to be jarred or it may be arranged at any desired point in the operating string. The sections A and B are connected for limited relative longitudinal movement and are provided with shoulders adapted to cooperate to effect jarring of one section by the other. The sections A and B are preferably telescoped or arranged one with the other. In the particular construction illustrated in the drawing, the upper section A is tubular and the lower section B extends into the section A.

The upper section A includes a main tubular portion v10 and a head or sub block 11 at its upper end. The sub block 11 is removably screw-threaded into the upper end of the main portion 10 'and is provided with an upwardly projecting screw threaded tapered pin 12 to facilitate connection with an operating-string. The block 11 is provided with la central longitudinal passage 13 communicating with the interior of the tubular portion 10. The main tubular portion l0 is an elongated member. A portion of reduced internal diameter is provided at the lower end of the portion 10 to provide an upwardly facing annular shoulder 14 on the interior of the section A.

The section B is adapted to be connected with the object to be jarred and includes a stem portion l5 slidable in the opening of the section A and a sub Aor connecting member 16 at itsA lower end. The connecting member 16 may be screw-threaded onto the lower end of the stem 15 and may have a downwardly projecting screw threaded pin 17 to facilitate connection with a iishing tool or operating string. The stem 15 is slidable in the opening 18 of the reduced lower end of the section A and projects upwardly into the interior of the tubular portion 10. An enlargement or head 19 is provided at the `upper end of the stem 15 within the tubular portion 10. The head 19 provides a downwardly facing annular shoulder 20 which is spaced from the shoulder 14 when the parts are in the unactuated position. The exterior of the head 19 slidably engages the inner walls-of thetubular portion 10.

It is preferred to connect the sections A and B against relative rotation. `In the case 4illustrated, the stem l5 of the section B is provided with longitudinal keys or splines 21 to slidably operate in keyways 22 in the opening of the reduced lower end portion of the part 1'0. Longitudinal grooves23may be provided in the walls of the opening'18to permit the escape of fluid trapped 'between the shoulders 14 and 20. In accordance with the preferred form of the invention, a fluid passage 24 is provided through the section B. The passage 24 extends longitudinally through the section 'B from one end to the other, having its upper end communicating .with vthe interior of the section A and its lower vend discharging at the lower end of the connecting member 16. The shoulders 14 and 20 cooperate to` limit the relative longitudinal movement of the sections A and B in one direction while the lower end of the section A is adapted to engage the connecting member 16 to limit the relative movement of the sections in the opposite direction. The shoulders 14 and 20 are adapted to cooperate orto be brought into engagement to provide ajarring action .when the latch means C is released.

The latch means C-operates to automatically release the sections A and B for `relative longitudinal movement upon a vpredetermined tensile strain being put on the tool. .The latch means C is preferably located within the tubularsection A between the upper end of the head 19 andthe sub block 11. The control means C includes, generally, two cooperating parts or members, one a latch on one section, and the other a block on the other section. In the efmbodiment of the invention illustrated in the drawing, a latch 25 is mounted on the section B to cooperate with a block 26 on the section A.

The latch 25 maybe directly connected to the section B. The lateh'25 may be mounted at the upper end of the enlargement or head 19 to project upwardly therefrom into the interior of the tubular part 10. The latch 25 may .include two spaced vertical links 27 pivotally connected to the head 19. The head 19 may be provided with recessesA 28 to receive the lower ends of the links 27, and the links 27 may be pivotally secured to the head 19 by suitable screws 29. A roller 30 is arranged between the upper ends of the links 27 to engage or cooperate with the blockv 26. 'The roller 30 may-be rotatably mounted on a pin 31 extending between the links 27.

In accordance with the preferred form of the invention means is provided for=urgingthe latch 25 toward the block 26 and for returning the latch 25 for cooperative engagement with the block-when the tool is reset after actuation. A

`leaf spring 32 may be mounted on the interior strain is exerted on the tool.

of the tubular portion 10 to engage the roller 30 and urge it toward the block 26. The spring 32 may have its lower portion secured to the interior of the tubular portion 10 by screws 34 and may be bowed upwardly and inwardly to engage the roller 30.

The block 26 is mounted on the interior of the tubular portion 10 to cooperate with the roller 30 of the latch 25. The .block 26 is -mounted to tilt or shift to cause disengagement oi the roller 30 when a predetermined longitudinal or tensile The block is mounted so that the roller 30 seats on or engages its upper end. The block 26 may be mountedon the -section A in various manners. In the particular case shown, the block 26 is pivotally supported on a carrier or bracket 35 mounted on theiinterior of the portion 10. The block 26 has a vertical rib 36 arranged between spacedparts of the bracket 35. A pin 37 may extend `betweenthe spaced parts of the bracket 35 to tiltably `or pivotally support the Yblock on the bracket.

In accordance ,with .the invention, .I provide means .for Vnormally .yieldingly holding the block 26 in ,position where lthe Vroller 30 vengages the upper `end'of `the block to hold the sections A and B against relative longitudinal movement. Thismeans operatesto retain ythe block 26 in a position to hold theroller against disengagement from 'the block until ra ypredetermined longitudinal `strain .is Vexerted yon the tool tending to bring the shoulders v14 and 20 together. The means for,yieldinglyholdingathe block 26 against movement is in the nature nof a spring means yeldingly holding the .blockincoo-perative engagement with :the roller 30. The means for resisting .movement of the block is such-that y,it is adapted to resist .an excessive or .heavy vstrain before ,permitting movement lof the `block 'to cause the releaseof the ,roller softhat the operating string Ais stretched `or elongated-,to provide the desired upward force .for bringing the shoulders 14 and 120 -into jarring engagement.

The means resisting movement; of the block is in the nature-of 1a vspring-,construction connectingrthe block k26 with the tubular portion l0 of the section A.` The iresisting means is -ia laminated structureor assembly-.ofapluralityy of leaf springs `38 .attached to the ablock 26 and projecting downwardly fromthe block. Thelowerfends of the group of springs38 are carried `byfasuitable support 40 secured to the `inner awalls .of the portion 10. The upperendsof :thesprings 38.seat in a lsocketiorfrecess-411in'the lower-end of theblock 26 andmayibe securedto'theiblock by a suitable screw or bolt A:42 screw-threaded intothe block. The lower endsbf the lsprings 38 are carried in a socket 43 in the upper-endrv of the support-46 and may besecuredin the socket by a bolt 144. The springs 38 extend downwardly and slightly outward from the .block 26 to the support A40. The springs 38 may beabowed outwardly somewhat 'as clearly illustrated yin the drawing. A stop -oradjusting screw 45 isthreaded through the wall of the portion y10 topengfge the assembly of springs 1,38 at a point vadjacent itslower end'to limit-the outwardbowing or ilexing of the lower-portion of the springs.

ing the latch means C and may be setltoypermit outwardbowing of the vsprings 38 `to disengage the,roller30"from the-block26 upon any desired strain abeing communicated through the springs.

Whenra Alongitudinalstrainis exerted on the The adjusting -screw45 `provides a meansfor adjust- F tooltending to bring the shoulders 14 and 20 together whenthe latchy means is set, the strain is communicated through the block 26 and latch 25.. The strain is directly communicated through the block 26 and the roller 30 of the latch 25. The roller 30 engages the upper side of the block 26 vat a point offset from the pivotal axis of the block so that the strain communicated to the block and latch tends to turn or pivot the block downwardly. The springs 38 resist this tendency of the block26 to pivot downwardly and are ar-v ranged in approximate tangential alignment with the direction of turning of the block to offer resistance to the shifting of the block to effectively hold the block against movement until the strain is very heavy. The springs 38 may be made to' effectively resist the substantially compressive strain to which they are subjected, and may be disposed or arranged to offer the proper resistance to the strain. `Upon the strain upon the tool reaching a predetermined degree, the springs 38 are bowed outwardly and the block 26 is shifted or turned downwardly so that the roller 30 is free to be operated off the upper end of the block 26. When the roller 30 is disengaged from the block 26, the sections A and B are free for relative movement. In practice, the tool is operated through an operating string which is stretched to a considerable extent when the strain is put on the tool, and upon releasing of the latch means C, it springs back to its normal length to provide a heavy upward force which is converted into an upward jarring action to the object connected with the section B through the engagement of the shoulders 14 and 20. To reset the tool or to move the parts to their normal positions after actuation, the section A is moved downwardly relative tc the section B so that the roller 30 is shifted into engagement with the upper end or the block 26 by the spring 32.

It is to be noted that the jarring tool provided by this invention is particularly simple of construction and operation. The tool embodies but few simple parts and the wearing parts, such as the latch 25 and the block 25, are readily replaceable. The tool may be operated by simple reciprocation of the operating string and the circulation of uid through the tool is not cut oi during its operation. It will be apparent how the set screw may be employed to vary the reaction of the springs 38 to the strains to which they are subjected so that the latch means C may be adjusted to trip upon any desired strain being imparted to the tool.

Having described only a typical preferred form of my invention, do not wish to limit myself to the specie details set forth, but wish to reserve to myself any changes or variations that may appear to those skilled in the art or fall within the scope of the following claims.

Having described my invention, I claim:

1. A well tool of the character described including, two sections connected for limited relative longitudinal movement, and means for releasably holding the sections against relative movement, said means being operable to release the sections upon a predetermined strain being applied to the sections tending to cause relative longitudinal movement between them, said means including, two cooperating parts, one a latch pivotally mounted on one section, the other a block releasably holding the latch and pivotally mounted on the other section to pivot on an axis stationary relative to said other section under a strain tending to move the sections longitudinally relative toone another, a spring attached to the block, and means rigidly connecting the spring to the said other section to yield-- means including, two cooperating parts, one aA block pivotally mounted on one section and having a side surface spaced from its pivotal axis, the other a latch pivotally mounted on the other section and engaging said side surface of the block, a spring attached to the block to extend from the block at a point substantially opposite to said surface relative to the pivotal axis of the block, and means 'attaching the spring to the first-mentioned section to yieldingly resist pivoting ofthe block when a strain is applied to the sections tending to move them longitudinally relative to one another.

3. A well tool of the character described including, two sections connected for limited relative longitudinal movement, and means for releasably holding the sections against relative movement, said means being operable to release the sections upon a predetermined strain being applied to the sections tending to cause relative longitudinal movement between them, said means including, two cooperating parts, one a latch mounted on one section, the other a block releasably holding the latch and pivotally mounted on the other section to pivot about an axis fixed relative to said other section under a strain tending to move the sections longitudinally relative to one another being exerted on the sections, a spring attached to the block and attached to the said other section to yieldingly resist shifting or" the block, andr means for adjusting the resistance of the spring.

4. A well tool of the character described including, two sections connected for limited relative longitudinal movement, and means for releasably holding the sections against relative movement, said means being operable to release the sections upon a predetermined strain being applied to the sections tending to cause relative longitudinal movement between them, said means including, two cooperating parts, one a latch mounted on one section, the other a block releasably holding the latch and pivotally mounted on the other section to pivot about an axis stationary relative to the said other section under a strain tending to move the sections longitudinally relative to one another being exerted on the sections, a spring attached to the block and attached to the said other section to yieldingly resist pivoting of the block, and means for adjusting the resistance oi the spring, including a screw on the said other section to engage the spring.

5. A jarring tool including two sections related for limited relative longitudinal movement, and means releasably holding the sections against relative longitudinal movement and operable to release the sections for relative longitudinal movement upon a predetermined strain being put on the sections, said means including a latch on one section, a block pivotally mounted on the other section and operable to releasably cooperate with the latch to hold the sections against relative movement, an elongated longitudinally bowed leaf spring -having `one end attached to the block, means rigidly connecting the other end of the spring to said other section whereby the spring resists pivotal movement of the block, and a screw for acting on the spring between its ends to regulate the action of lthe spring.

6. A jarring tool including two sections related for limited relative longitudinal movement, and means releasa-bly holding the sections against relative longitudinal movement and 0perable to release the sections for relative longitudinal movement upon a predetermined strain being put on the sections, said means including a latch on one section, a block pivotally mounted on the vother section to releasably engage the latch to hold the sectionsagainst relativemovement, and an elongated longitudinally bowed leaf spring having one end attached to the said other section and the other end `attached to the block, and means for adjusting the resistance of the spring including a screwthreaded member for engaging the spring intermediate its ends.

7. A Well tool of the character described including, two -sectionsconnected for limited relat-ive longitudinal movement, and means for releasably holding the sections against relative movement, said means being operable to release the `sections upon a predetermined strain being applied to the sections tending to cause relative longitudinal movement between them, said means including, two cooperating parts, one a latch pivotally mounted on one sectiomthe vother a block releasably holding the latch and pivotajlly mounted on the other section to pivot under a longitudinal strain on the sections, yieldable means resisting `pivoting of the block, and means for adjusting the last mentioned means to cause the latch and block to disengage under different strains on i the sections.

IRA J. MCCULLOUGH. 

